System and method for creating a formatted building database manipulator with layers

ABSTRACT

A Building Database Manipulator to build databases for a variety of physical environments including definitions of buildings, terrain and other site parameters, by scanning in or rapidly editing data. Raster scans may be entered or object files in various formats may be used as input. Detailed information is stored in the drawing database about the object&#39;s location, radio frequency attenuation, color, and other physical information such as electrical characteristics and intersections of the object with the ground, floors, ceilings, and other objects when objects are formatted in a drawing. The formatting process is strictly two-dimensional in nature, but the resulting drawing is a true three-dimensional environment. The user sees the three-dimensional building structure by altering the views. The resulting database may be used in a variety of modeling applications, but is especially useful for engineering, planning and management tools for in-building or microcell wireless systems. Grouping objects in layers allows for simultaneous conversion of all objects in one layer to have certain predetermined attributes (e.g., converting objects to be made from glass versus cement; converting objects within a layer to have a uniform, smaller or larger, height or width dimension).

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part (CIP) application ofU.S. Ser. No. 09/318,841 filed May 26, 1999, and the complete contentsof that application are herein incorporated by reference.

DESCRIPTION BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention generally relates to database developmentusing computer aided design and, more particularly, to manipulating datafrom any environment in the world (e.g. cities, buildings, canpuses,floors within a building, objects in an outdoor setting, etc.) toconstruct an electronic building database that can be used to generatedefinitions of the user's building and site parameters and used withwireless communication system modeling and engineering planningproducts.

[0004] 2. Background Description

[0005] As wireless communications use increases, radio frequency (RF)coverage within buildings and signal penetration into buildings fromoutside transmitting sources has quickly become an important designissue for wireless engineers who must design and deploy cellulartelephone systems, paging systems, or new wireless systems andtechnologies such as personal communication networks or wireless localarea networks. Designers are frequently requested to determine if aradio transceiver location, or base station cell site can providereliable service throughout an entire city, an office, building, arenaor campus. A common problem for wireless systems is inadequate coverage,or a “dead zone,” in a specific location, such as a conference room. Itis now understood that an indoor wireless PBX (private branch exchange)system or wireless local area network (WLAN) can be rendered useless byinterference from nearby, similar systems. The costs of in-building andmicrocell devices which provide wireless coverage within a 2 kilometerradius are diminishing, and the workload for RF engineers andtechnicians to install these on-premises systems is increasing sharply.Rapid engineering design and deployment methods for microcell andin-building wireless systems are vital for cost-efficient build-out.

[0006] Analyzing radio signal coverage penetration and interference isof critical importance for a number of reasons. A design engineer mustdetermine if an existing outdoor large scale wireless system, ormacrocell, will provide sufficient coverage throughout a building, orgroup of buildings (i.e., a campus). Alternatively, wireless engineersmust determine whether local area coverage will be adequatelysupplemented by other existing macrocells, or whether indoor wirelesstransceivers, or picocells, must be added. The placement of these cellsis critical from both a cost and performance standpoint. If an indoorwireless system is being planned that interferes with signals from anoutdoor macrocell, the design engineer must predict how muchinterference can be expected and where it will manifest itself withinthe building, or group of buildings. Also, providing a wireless systemthat minimizes equipment infrastructure cost as well as installationcost is of significant economic importance. As in-building and microcellwireless systems proliferate, these issues must be resolved quickly,easily, and inexpensively, in a systematic and repeatable manner.

[0007] There are many computer aided design (CAD) products on the marketthat can be used to design the environment used in one's place ofbusiness or campus. WiSE from Lucent Technology, Inc., SignalPro fromEDX, PLAnet by Mobile Systems International, Inc., and TEMS and TEMSLight from Ericsson are examples of wireless CAD products. In practice,however, a pre-existing building or campus is designed only on paper anda database of parameters defining the environment does not readilyexist. It has been difficult, if not generally impossible, to gatherthis disparate information and manipulate the data for the purposes ofplanning and implementation of indoor and outdoor RF wirelesscommunication systems, and each new environment requires tedious manualdata formatting in order to run with computer generated wirelessprediction models. Recent research efforts by AT&T Laboratories,Brooklyn Polytechnic, and Virginia Tech, are described in papers andtechnical reports entitled “Radio Propagation Measurements andPrediction Using Three-dimensional Ray Tracing in Urban Environments at908 MHZ and 1.9 GHz,” (IEEE Transactions on Vehicular Technology, VOL.48, No. 3, May 1999), by S. Kim, B. J. Guarino, Jr., T. M. Willis III,V. Erceg, S. J. Fortune, R. A. Valenzuela, L. W. Thomas, J. Ling, and J.D. Moore, (hereinafter “Radio Propagation”); “Achievable Accuracy ofSite-Specific Path-Loss Predictions in Residential Environments,” (IEEETransactions on Vehicular Technology, VOL. 48, No. 3, May 1999), by L.Piazzi and H. L. Bertoni; “Measurements and Models for Radio Path Lossand Penetration Loss In and Around Homes and Trees at 5.85 Ghz,” (IEEETransactions on Communications, Vol. 46, No. 11, November 1998), by G.Durgin, T. S. Rappaport, and H. Xu; “Radio Propagation PredictionTechniques and Computer-Aided Channel Modeling for Embedded WirelessMicrosystems,” ARPA Annual Report, MPRG Technical Report MPRG-TR-94-12,July 1994, 14 pp., Virginia Tech, Blacksburg, by T. S. Rappaport, M. P.Koushik, J. C. Liberti, C. Pendyala, and T. P. Subramanian; “RadioPropagation Prediction Techniques and Computer-Aided Channel Modelingfor Embedded Wireless Microsystems,” MPRG Technical ReportMPRG-TR-95-08, July 1995, 13 pp., Virginia Tech, Blacksburg, by T. S.Rappaport, M. P. Koushik, C. Carter, and M. Ahmed; “Use of TopographicMaps with Building Information to Determine Antenna Placements and GPSSatellite Coverage for Radio Detection & Tracking in UrbanEnvironments,” MPRG Technical Report MPRG-TR-95-14, Sep. 15, 1995, 27pp., Virginia Tech, Blacksburg, by T. S. Rappaport, M. P. Koushik, M.Ahmed, C. Carter, B. Newhall, and N. Zhang; “Use of Topographic Mapswith Building Information to Determine Antenna Placement for RadioDetection and Tracking in Urban Environments,” MPRG Technical ReportMPRG-TR-95-19, November 1995, 184 pp., Virginia Tech, Blacksburg, by M.Ahmed, K. Blankenship, C. Carter, P. Koushik, W. Newhall, R. Skidmore,N. Zhang and T. S. Rappaport; “A Comprehensive In-Building andMicrocellular Wireless Communications System Design Tool,”MPRG-TR-97-13, June 1997, 122 pp., Virginia Tech, Blacksburg, by R. R.Skidmore and T. S. Rappaport; “Predicted Path Loss for Rosslyn, Va.,”MPRG-TR-94-20, Dec. 9, 1994, 19 pp., Virginia Tech, Blacksburg, by S.Sandhu, P. Koushik, and T. S. Rappaport; “Predicted Path Loss forRosslyn, Va., Second set of predictions for ORD Project on Site SpecificPropagation Prediction” MPRG-TR-95-03, Mar. 5, 1995, 51 pp., VirginiaTech, Blacksburg, by S. Sandhu, P. Koushik, and T. S. Rappaport. Thesepapers and technical reports are illustrative of the state of the art insite-specific propagation modeling and show the difficulty in obtainingdatabases for city environments, such as Rosslyn, Va. While the abovepapers describe a research comparison of measured vs. predicted signalcoverage, the works do not demonstrate a systematic, repeatable and fastmethodology for creating an environmental database, nor do they report amethod for visualizing and placing various environmental objects thatare required to model the propagation of RF signals in the deployment ofa wireless system in that environment.

SUMMARY OF THE INVENTION

[0008] It is therefore an object of the invention to provide a methodfor manipulating drawings and electronic files to build databases foruse in planning the positioning of components and for designing,installing and optimizing a wireless communication system. In themethod, raster scanned images of an environment may be entered or objectfiles in various formats may be used as input to define an environmentin which a wireless system is to be implemented. Detailed informationabout the location, radio frequency attenuation, color, and otherphysical information of an object, such as intersections of the objectwith the ground, floors, ceilings, and other objects in the environmentis stored in a drawing database.

[0009] It is another object of the invention to provide a computerizeddrawing in a true three-dimensional environment based on input datawhich is strictly two-dimensional in nature. The user sees thethree-dimensional drawing structure on a computer display by alteringthe views.

[0010] It is another object of the invention to provide the resultingdatabase of the inventive method in a form easily used in a variety ofmodeling applications, especially forms useful for engineering, planningand management tools for wireless systems.

[0011] It is another object of the invention to support a universalmethod for creating and editing and transporting environmental databasesfor wireless communication system design, prediction, measurement andoptimization. A systematic and automated method for producing a 3-Denvironmental database that is reproduceable and transportable betweenmany different wireless system prediction models, measurement devices,and optimization methods has value and is a marked improvement overpresent day systems.

[0012] According to the invention, pre-existing data for a desiredenvironment may be scanned in, traced or translated from anotherelectronic format as a short-cut to provide a partial definition for theenvironment. The partial or empty environment is then refined using aspecialized drawing program to enter entities and objects that fullydefine the environment in terms of floors, partitions, obstructions, andother data required for engineering planning of a wirelesscommunications network in the environment. The input data are generallytwo dimensional (2D) representations of the environment. When ceilingheight, elevation above sea level, or partition height data is entered,the drawing may then automatically be viewed in three-dimensions (3D).This 3D representation enables the design engineer to visually verifyany parameters incorrectly entered. The definition of the environment,or drawings, maps or other data are verified and the design engineer isautomatically prompted to enter missing or inconsistent information.Once the drawing(s) have been verified, the data defining theenvironment may be used by a variety of tools, models, wirelesspropagation prediction methods, measurement products or optimizationprocedures that require information about an environment's terrainlevels, physical make up, and specific location of floors, walls,foliage or other obstruction and partition structures. Anything thatimpedes or otherwise affects the propagation of radio wave energy mustbe considered when predicting the performance of a wirelesscommunication system in the environment, and the present methodologyprovides a simplified mechanism for collecting and editing thisinformation in a readily usable form. The method for constructing andmanipulating an indoor or outdoor environment is useful not only forwireless communication designers, but may also be useful for otherapplications, as well.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The foregoing and other objects, aspects and advantages will bebetter understood from the following detailed description of a preferredembodiment of the invention with reference to the drawings, in which:

[0014]FIG. 1 is a flow diagram of the general method of the invention;

[0015]FIG. 2 is a representation of a typical building floor plan;

[0016]FIG. 3 is a representation of a raster image of a house;

[0017]FIG. 4 is flow diagram of a method for generating drawings frompre-existing computer aided design (CAD) drawings;

[0018]FIG. 5 is a flow diagram of a method for creating a drawingwithout pre-existing information;

[0019]FIG. 6A is a flow diagram of a method for generating drawings frompre-existing raster images to be used only with distant dependentwireless system performance prediction models;

[0020]FIG. 6B is a flow diagram of a method for generating drawings frompre-existing raster images to be used with any number of wireless systemperformance prediction models;

[0021]FIGS. 7A through 7F show examples of methods for snapping anobject to a grid, or other desired location on a drawing;

[0022]FIG. 8 is a schematic drawing of a computer dialog windowillustrating the layers contemplated by this invention; and

[0023]FIG. 9 is a schematic drawing, in 3-D, of the same CAD file shownin FIG. 8 following the automatic processing of groups of objects in anyone layer according to this invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0024] The present invention is used to build databases for use withmodeling and engineering planning and automated design products. Thecurrent embodiment permits repeatable, reproduceable computerrepresentation that may be transported or exported into many standardfile formats and is designed specifically for use with the SitePlannersuite of products available from Wireless Valley Communications, Inc. ofBlacksburg, Va. However, it will be apparent to one skilled in the artthat the method could be practiced with other products either now knownor to be developed in the future. (SitePlanner is a trademark ofWireless Valley Communications, Inc.)

[0025] Referring now to the drawings, and more particularly to FIG. 1,there is shown a flow diagram for the method of the present invention.In order to build a specially formatted database that contains datanecessary and sufficient for input into an engineering model, adefinition of the desired environment must first be built. First,existing data is entered into the system database in function block 101.This data may be in a variety of formats, as described in detail later.Because this existing data may be in a format which embodies unnecessaryadditional data, legends, map layers or text, unneeded objects areremoved from the database in function block 102. The existing objectsare then formatted and embellished with additional information infunction block 103. Objects may include simple lines, representing wallsor the sides of buildings or they may be polygons or polylines whichrepresent trees, foliage, buildings, or other obstructions. An arbitrarynumber of objects may be drawn, traced, or moved using CAD commandswhich have a specific representation. In the preferred embodiment, eachobject or the group of objects saved in a file format known as “.DWG”which is developed by AutoDesk, Inc. However, it would be apparent toone skilled in the art how to practice this invention with otherapplications and tools using other formats. If additional objects areneeded to describe the environment, they are also added to the databasehere. In the event that there is no pre-existing data, and the databasemust be built from scratch, the process may begin at this point,skipping steps 101 and 102.

[0026] Once the data has been entered, the user may optionally displaythe 2D data as a 3D representation in function block 105. The 3D viewcan be displayed at any time after entering height data, at the user'sdiscretion.

[0027] Once the user has entered all of the data, a verification of thedrawing may be performed in function block 104. At this point theprocess does a step-by-step analysis of the environment defined in thedatabase to determine whether any data is missing. The inventionprovides an interactive feedback to the engineer and prompts the user asto where scaling and alignment are required, etc. While the preferredembodiment is described in detail, it should be evident to one skilledin the art that alternative methods such as totally automatedverification may be possible. Because any engineering planning toolrequires a specific set of information to operate optimally andefficiently, verification is important. The user is prompted toaffirmatively declare that each piece of desired data has been enteredand verified for proper format. If there are missing data, the user maythen return to step 103 to enter additional necessary objects beforerunning the verification procedure in function block 104, again. Thisstep provides automatic verification guidance and prompts the user withfeedback.

[0028] Once the drawing has been verified, the data is stored in thedatabase in function block 106 or can be exported for use in anapplication that does not read directly from the database. Thisspecially formatted data includes all information necessary to describethe building, site or campus environment.

[0029] While the above description generally describes the method of theinvention, a more detailed description follows. The current embodiment,Building Database Manipulator (BDM), has been designed to operateintegrally with the SitePlanner suite of products. Therefore, a detailedexample of how each step is performed will use this embodiment as afoundation for discussion. However, it should be understood that the BDMcould be used with other wireless communications propagation models(e.g. ray-tracing models or statistical models), other wirelessprediction tools (e.g., Lucent Technologies WiSE, EDX SignalPro™,Ericsson TEMS, MSI PLAnet), or measurement tools now available (e.g., awireless LAN transceiver, a spectrum analyzer, or any wirelessmeasurement device such as a ZK Celltest 836 or a Berkeley VaritronicsChamp receiver), or developed in the future. (BDM is a trademark ofWireless Valley Communications, Inc. SignalPro is a Trademark of EDX.PLAnet is a trademark of Mobile Systems International.)

[0030] Wireless prediction modeling software will typically utilize asite-specific database format, meaning that the database is specific tothe area/environment it represents. This database can be thought of asbeing a collection of buildings and terrain, properly scaled andpositioned in three-dimensional (3D) space relative to one another. Inturn, each building is a collection of the floors that it houses (e.g.,a nine story building has nine floors). FIG. 2 shows a typical buildingfloor plan as it may be entered into the database. Each floor is acollection of obstructions/partitions. An obstruction/partition isanything that impedes or otherwise affects the propagation of radio waveenergy, and thus must be considered when predicting the performance of awireless communication system in the environment. For example, concretewalls, brick walls, sheetrock walls, doors, windows, large filingcabinets, and many others are all obstructions/partitions. At the sametime, a large crowd of people, varying terrain, or foliage could also beconsidered obstruction/partitions.

[0031] The SitePlanner products, specifically, utilize a speciallyformatted vector database format, meaning that it consists of lines andpolygons rather than individual pixels (as in a raster format). Thearrangement of lines and polygons in the database corresponds toobstructions/partitions in the environment. For example, a line in thedatabase could represent a wall, a door, or some otherobstruction/partition in the modeled environment.

[0032] Obstructions/partitions are classified into categories. The usermay define different categories of obstructions/partitions. A categoryis defined by a textual description (e.g., “External Brick Walls”), avertical height (i.e., how tall is the wall), a color (to quicklydistinguish it from entities belonging to other categories while viewingthe drawing), and electromagnetic properties (discussed in furtherdetail later). The category to which a given drawing entity (where anentity is either a line or polygon) has been assigned defines the typeof obstruction/partition it represents. For example, if a given line hasbeen assigned to the user-defined category of “Sheetrock Walls,” then itshares the characteristics given by the user to all other entitieswithin that category throughout the entire database drawing. The processof either creating new entities or changing the category to which theentity belongs is a simple point-and-click process using a mouse orother positioning device, by linking entities to a particular userdefined category of partitions. The preferred embodiment allows thephysical, electrical, and aesthetic characteristics of entities of thesame category to be individually or collectively edited. Categorydesignation is carried out by assigning a particular numerical value tothe field of each entity, wherein the field is specified as part of thedrawing database.

[0033] From the standpoint of radio wave propagation, eachobstruction/partition in an environment (i.e., each entity in thedrawing, or the equivalent thereof), has several electromagneticproperties that directly affect it. When a radio wave signal intersectsa physical surface, several things occur. A certain percentage of theradio wave reflects off of the surface and continues along an alteredtrajectory. A certain percentage of the radio wave penetrates throughthe surface and continues along its course. A certain percentage of theradio wave is scattered once it strikes the surface. The electromagneticproperties given to the obstruction/partition categories, when used inconjunction with known electromagnetic theory, define this interactionwithin the environment. Each category has parameters that include anattenuation factor, surface roughness, and reflectivity. The attenuationfactor determines the amount of power a radio signal loses when itpenetrates through an entity of the given type. The reflectivitydetermines the amount of the radio signal that is reflected from theentity (as opposed to penetrating through it). The surface roughnessprovides information used to determine how much of the radio signal isscattered upon striking an entity of the given type.

[0034] As mentioned above, the parameters given to each category fullydefine the entities contained within it. Altering the parameters of acategory directly affects all entities assigned to it. This greatlysimplifies the tedium of database creation for site-specific modeling.

[0035] The method used to predict and optimize antenna positioning in adesired environment uses a number of models, such as those described inthe papers: “Interactive Coverage Region and System Design Simulationfor Wireless Communication Systems in Multi-floored Indoor Environments,SMT Plus,” IEEE ICUPC '96 Proceedings, by R. R. Skidmore, T. S.Rappaport, and L. Abbott; “Achievable Accuracy of Site-SpecificPath-Loss Predictions in Residential Environments,” (IEEE Transactionson Vehicular Technology, VOL. 48, No. 3, May 1999), by L. Piazzi and H.L. Bertoni (hereinafter “Achievable Accuracy”); “Wireless Propagation inBuildings: A Statistical Scattering Approach,” (IEEE Transactions onVehicular Technology, VOL. 48, No. 3, May 1999), by D. Ullmo and H. U.Baranger; “Site-Specific Propagation Prediction for Wireless In-BuildingPersonal Communication System Design,” (IEEE Transactions on VehicularTechnology, VOL. 43, No. 4, November 1994), by S. Y. Seidel and T. S.Rappaport; “Antenna Effects on Indoor Obstructed Wireless Channels and aDeterministic Image-Based Wide-Band Propagation Model for In-BuildingPersonal Communication Systems,” (International Journal of WirelessInformation Networks. Vol. 1, No. 1, 1994), by C. M. P. Ho, T. S.Rappaport and M. P. Koushik; and “Interactive Computation of CoverageRegions for Wireless Communication in Multifloored Indoor Environments,”(IEEE Journal on Selected Areas in Communication, Vol 14, No. 3, April1996), by M. A. Panjwani, A. L. Abbott and T. S. Rappaport;“Measurements and Models for Radio Path Loss and Penetration Loss In andAround Homes and Trees at 5.85 Ghz,” (IEEE Transactions onCommunications, Vol. 46, No. 11, November 1998), by G. Durgin, T. S.Rappaport, and H. Xu, and previously cited references, all of which arehereby incorporated by reference. Some simple models are also brieflydescribed in “SitePlanner 3.16 for Windows 95/98/NT User's Manual”(Wireless Valley Communications, Inc. 1999), hereby incorporated byreference. It would be apparent to one skilled in the art how to applyother models to this method.

[0036] In order to build a database that can be used in site-specificmodeling, as done, for instance, in SitePlanner, or in equivalentprograms now known or later developed, or similarly in otherapplications, one can either build each entity from scratch or startwith a full or partial definition of the environment in some format. Thepresent invention offers many solutions to ease the incorporation ofpreviously drawn or scanned images of building floor plans to accomplishstep 101 of the method, as shown in FIG. 1. A wide variety ofpre-existing formats such as a paper map, an electronic map, ablueprint, and existing CAD drawing, a bitmap image, or some otherrepresentation, are used to obtain environmental information. Mostcommonly, this information is available in some form of electronicbuilding blueprint or map information and in the case of buildings, isoften supplied one floor at a time. That is, a building blueprintusually involves a separate blueprint or other piece of information foreach building floor. Two possible formats for this information areraster and vector. The present invention extracts environmental datafrom both formats. One skilled in the art would see how both raster andvector data (e.g., USGS raster terrain data with vector buildingoverlays) could be combined using the present invention.

[0037] Raster drawings or maps are collections of individually coloredpoints (or “pixels”) that, when viewed as a whole, form a picturerepresentation of the environment. FIG. 3 shows a photograph of a house110 made up of a series of colored pixels to represent the appearance ofa house (appearing here in black and white). A raster image or mapreferences the pixels in a specific grid rather than vectors. Therefore,raster images do not contain detailed information about objects.

[0038] The present invention allows raster images to be copied, moved,or clipped. Using the present invention, one can modify an image withgrip modes, adjust an image for contrast, clip the image with arectangle or polygon, or use an image as a cutting edge for a trim.Examples of raster formats processed by the preferred embodiment of thepresent invention include, but are not limited to, Windows Bitmaps(BMP), Joint Photographic Experts Group format (JPEG), GraphicalInterchange Format (GIF), Tagged-Image File Format (TIFF), Targa format(TGA), PICT, and Postscript. Raster drawings of any type may beconverted into vector drawings, or other vector data basedrepresentations. The process involves using the imported raster drawing(which is really just an image) as a backdrop, and then tracing over itwith a mouse or other positioning device, and adding new entities (linesand polygons), to generate a formatted database/drawing.

[0039] Vector drawings are collections of individual lines and polygons.Examples of vector formats include AutoCAD drawing files (DWG), AutodeskDrawing Exchange files (DXF), and Windows Metafiles (WMF). Becausevector drawings already consist of lines and polygons, converting theminto a format used by the present invention is straightforward. In thepreferred embodiment, vector drawings are converted into BDM formatdrawings by simply loading them, selecting lines and/or polygons withinthe drawing, and then assigning the selected entities to a givencategory.

[0040] When using pre-existing data formats, it is probable that the mapor drawing will contain information that is unneeded for the modelingand prediction steps. Therefore, one should remove unneeded objects fromthe drawing, as shown in step 102 of FIG. 1.

[0041] In addition to importing images and drawings, a collection ofcommands that permit users to draw new floor plans to accomplish step103 of the method is provided. Multiple floor plans may be combined intothree-dimensional, multi-floored drawing databases for use in themethod, also in step 103.

[0042] During the process of creating and formatting building databases,one may view the current drawing in 3D, as shown in step 105 of FIG. 1.Each obstruction/partition category has an associated height parameterthat defines the vertical dimension of each entity in the givencategory. By creating a new entity of a given category or converting anentity from or between categories, the vertical dimension of the newentity is automatically adjusted to match that specified for thecategory. Thus, if the invention processes a 2D vector drawing (i.e., adrawing with individually selectable lines and polygons), selecting anentity and assigning it to a given category carries out the conversionbetween 2D and 3D automatically. If the invention processes a rasterdrawing (i.e., a bitmap or similar format drawing that consists ofindividual colored pixels), the drawing can be imported and “tracedover”, where with the creation of each new entity, the category againdefines the vertical dimension given to the entity.

[0043] Each building floor can itself be thought of as a category thatencapsulates the obstruction/partition categories defined by the user.Each floor of a building has an associated ceiling height.Alternatively, entire buildings may be represented with a buildingheight. For the case of a multifloor building, the ceiling heights givento each floor in a building defines the vertical separation betweenthem. Thus, the ceiling height parameter of a given floor is used tocorrectly position, vertically in space, each entity located on thefloor relative to the entities located on other floors of the building.

[0044] Once the height of a given obstruction/partition category and/orthe ceiling height of a given floor is adjusted, the 3D structure or thedrawing database is altered automatically, as appropriate. This is amajor improvement over other 3D techniques simply from a speed and easeof use point of view. It is much easier to construct a building in 2Dusing lines and polygons whose vertical dimension is handledautomatically, as in the present invention, than to model the samebuilding in 3D using slanted or vertical planes, as is done in othersystems, such as suggested in the “Radio Propagation” and “AchievableAccuracy” papers, cited above. The 3D view enables the user to verifythe building structure (i.e., that the vertical dimension of anobstruction/partition category has not been inadvertently specifiedincorrectly) and provides a unique perspective that is ultimately usefulwhen viewing wireless prediction or measurement data for evaluation ofthe performance of the communication system being modeled.

[0045] Once an environment has been specified and defined as objects,and a visual verification of the 3D drawing is complete, a fullverification of this definition is performed in step 104, as shown inFIG. 1. The engineer or designer selects the Final Drawing Checkprocedure to ensure that all of the steps necessary to create a fullyfunctional model of the desired building environment have been correctlyperformed. These steps include ensuring that the modeled environment isproperly scaled and that the separate floors of the building arevisually aligned in 3D space. Certain drawing structures and informationcan also be automatically detected. For example, the number of floors ina given building, the number and types of obstruction/partitioncategories and the entities assigned to each type, whether or not theuser has already verified the drawing previously, and what (if any)activity has been done to the drawing database by the other SitePlanner—tool suite members can be automatically detected and reported to theuser.

[0046] To obtain wireless system performance predictions using datagenerated with the present invention, as disclosed in the co-pendingapplication Ser. Nos. 09/318,842 and 09/318,840, one preferably uses thepresent method for the preparation of building databases. Depending onthe chosen wireless system propagation or performance prediction model,important information is needed such as physical distances, partitionlocations, floor locations, and the numbers of floors and partitions.Standard architectural drawings, like scanned images, do not contain thenecessary database information. Therefore, building a verified databasefor use in the selected wireless system propagation or performanceprediction model is essential to ensure the best results.

[0047] Computer Aided Design (CAD) programs create vector graphics, madeof lines and curves defined by mathematical objects called vectors.Vectors describe graphics according to their geometric characteristics.For example, a wheel in a vector graphic is made up of a mathematicaldefinition of a circle drawn with a certain radius, thickness, color,and specific location. A user can move, resize, or change the color ofthe wheel without losing the quality of the graphic.

[0048] The present invention utilizes the vector information of importedmaps, drawings or electronic images and file formats, as well asinformation input by users, to build complex 3-D representations andvector based databases. The preferred embodiment utilizes the drawingcommands from AutoCAD, a product of AutoDesk, Inc. of San Rafael, Calif.It would be apparent to one skilled in the art that any other vectorizeddrawing tool, either now known or to be invented could be used as analternative in the practice of the present invention. The process ofinputting and converting the environmental information into a databaseis referred to as formatting. The present invention facilitates theformatting of objects in a drawing, and also stores detailed informationin the drawing database about the object's location, attenuation factor,color, and other physical and electrical information such asreflectivity, or intersections of the object with floors, ceilings, andother objects.

[0049] The present invention may scan and format environmentalinformation if a vector drawing of the environment does not exist. Ifformatted vector drawings do exist, the method of the invention providesmany ways for these drawings to be formatted into a useful format.Generally, two “starting points” exist when working with vectordrawings. These starting points are briefly discussed in the followingbulleted list.

[0050] Starting with a previously drawn (CAD) floor plan, and

[0051] Starting from scratch.

[0052] In order to create a vectorized drawing of a desired environment,it is desired to utilize a number of drawing tools. The present methodprovides the user with a wide range of commands which have been craftedfor rapid database creation and manipulation, as described below. Manyof these commands rely on specific combinations of AutoCAD drawingcommands which are sequentially executed without the user having to knowthe specific CAD commands. It should be apparent to one skilled in artthat the method for creating drawings, as described below, could bepracticed with other products either now known or to be developed in thefuture.

[0053] View Formatted Information command—This command invokes a listbox that contains a list of formatted floors in a drawing.

[0054] Hide Formatted Information command—This command allows a user tohide partitions that have been previously formatted.

[0055] View Unformatted Information command—This command works in asimilar manner as the View Formatted Information command. A list box ofavailable layers in the drawing that are not formatted layers isdisplayed.

[0056] Toggle Orthogonal Draw On/Off command—With the default cursorsnap setup, ORTHO mode (ON) constrains cursor movement to horizontal andvertical directions (90 degrees).

[0057] Display Grid command—This command allows the user to specify gridspacing, or to turn on/off snap and aspect options. It also allows theuser to specify the spacing value between grid lines. The user may turnthe grid on or off.

[0058] Snap—Sets the grid spacing to the current snap interval.

[0059] Aspect—Sets the grid to a different spacing in X and Ydirections.

[0060] Cursor Snap command—This command prompts the user with “Snapspacing or ON/OFF/Aspect/Rotate/Style <0.5000>:”

[0061] Spacing—Activates Snap mode with the specified value.

[0062] ON—Activates Snap mode using the current snap grid resolution,rotation, and style.

[0063] OFF—Turns off Snap mode but retains the values and modes.

[0064] Aspect—Specifies differing X and Y spacing for the snap grid.This option is not available if the current snap style is Isometric.

[0065] Rotate—Sets the rotation of the snap grid with respect to thedrawing and the display screen. The user specifies a rotation anglebetween −90 and 90 degrees. A positive angle rotates the gridcounterclockwise about its base point. A negative angle rotates the gridclockwise.

[0066] Base point <current>: The user specifies a point

[0067] Rotation angle ˜current>: The user specifies an angle

[0068] Style—The user specifies the format of the Snap grid, which isstandard or isometric.

[0069] Standard—Displays a rectangular grid that is parallel to the XYplane of the current Universal Coordinate System of the drawingdatabase. X and Y spacing may differ.

[0070] Isometric—Displays an isometric grid, in which the grid pointsare initially at 30- and 150-degree angles. Isometric snap can berotated but cannot have different Aspect values.

[0071] Object Selection Snap command—This command allows the user toselect points in the drawing. One should note that when more than onecheck box option is selected, the invention applies the selected snapmodes to return a point closest to the center of the aperture box.

[0072] The Snap procedure is especially useful in drawing the floors ofthe environment when tracing raster images and drawing from scratch.FIGS. 7A through 7F illustrate the various snapping procedures which areused by AutoCAD and known to those skilled in the art. For instance, theEndpoint option snaps to the closest endpoint of an entity as shown inFIG. 7A. The Midpoint option snaps to the midpoint of an entity as shownin FIG. 7B. The Perpendicular Node Nearest Intersection option snaps toa point perpendicular to an entity as shown in FIG. 7C. The node optionsnaps to a point object as shown in FIG. 7D. The Nearest option snaps tothe nearest point on an entity. The Intersection option snaps theintersection of two or more entities as shown in FIG. 7E. The ApparentIntersection option includes two separate snap modes: ApparentIntersection and Extended Apparent Intersection. The user can locateIntersection and Extended Intersection snap points while runningApparent Intersection object snap mode.

[0073] Apparent Intersection snaps to the apparent intersection of twoentities that do not intersect in 3D space, but might appear tointersect onscreen. Extended Apparent Intersection snaps to theimaginary intersection of two objects that would appear to intersect ifthe objects were extended along their natural paths, as shown in FIG.7F.

[0074] The Quick option snaps to the first snap point on the firstobject found. Quick must be used in conjunction with other object snapmodes.

[0075] Other useful commands are described below:

[0076] Show Distance Between Points command—This command prompts theuser to select two points in a drawing, after which the distance thepoints are display.

[0077] Break/Ungroup Entities command—This command allows the user toungroup and break apart objects.

[0078] Purge command—In addition to the graphic objects used by thepresent method, there are several types of non-graphical objects thatare stored in drawing files. These objects have descriptive designationsassociated with them; for example blocks, layers, groups, and dimensionstyles. In most cases the user names objects as they are created, andthey can later be renamed. Names are stored in symbol tables. When anamed object is specified on the command line or selected from a dialogbox, the name and associated data of the object is referenced in thesymbol table. Unused, unreferenced named objects can be purged from adrawing at any time during an editing session. Purging reduces drawingsize, and therefore, the memory requirements for working with thedrawing. Objects that are referenced by other objects cannot be purged.All objects may be purged at once, or the user can select a category ofobject to purge such as: Linetypes, Text Styles, Dimension Styles,Muitiline Styles, Blocks, and Shapes.

[0079] Drawing Utilities command—This command allows the user to auditthe drawing or recover from a corrupted drawing.

[0080] Alternately, the invention supports automated processing of CADdrawing files to generate a 3-D environmental model. This functionalityutilizes layers that are specified within the CAD drawing file toautomatically convert the graphical entities defined within the CAD fileto three-dimensional partitions/obstructions within the 3-Denvironmental model of the facility. Layers are collections of graphicaldrawing entities that have been grouped by an architect or other CADuser to serve some descriptive purpose regarding the facility. Forexample, all windows in a CAD drawing file of a facility could begrouped on a certain layer, while all the doors of a facility could begrouped onto a different layer. By referencing a layer that is definedin a CAD file, all entities that are grouped to form that layer are alsoreferenced. Therefore, layers enable quick access to entities that maybe similar in function within a CAD drawing file. Textual labels denotedifferent layers; therefore, all layers in a CAD drawing file must haveunique textual labels assigned to them. For example, all windows in aCAD drawing file may be grouped on layer “Windows”, whereas all doorsmay be grouped on layer “Doors”. By referencing the textual label givento a layer, a CAD user may automatically reference all of the individualgraphical entities that comprise the layer.

[0081] Although the given description of layers describes theimplementation of collections of graphical entities within AutoCAD®, apopular CAD software tool now available, one skilled in the art wouldunderstand that collections of graphical entities in CAD drawing filesother than AutoCAD® files could be utilized in a similar fashion. Thepresent invention includes functionality that utilizes layers within aCAD drawing file to automate the processing to convert the CAD drawingfile into a 3-D environmental model of a facility. The process includesthe ability to automatically convert all graphical entities that aregrouped onto a given layer within a CAD drawing file intothree-dimensional partitions/obstructions within the 3-D environmentalmodel. This is very advantageous as it eliminates the need toindividually select the graphical entities that comprise the givenlayer. Instead, by identifying the layer the desired action is appliedto all graphical entities that comprise the layer. In addition toautomatically processing all graphical entities comprising a selectedlayer into their three-dimensional partition/obstruction counterpartswithin the 3-D environmental model, the designer may elect toautomatically delete all graphical entities on a given layer, or changethe visibility of the entities on a given layer.

[0082] The automated processing of graphical entities that have beengrouped into layers in CAD drawing files is available in the presentinvention by accessing pull-down menus and commands. Computer dialogwindows are displayed that manage the automatic processing of thedrawing layers in a CAD file. Referring to FIG. 8, there is shown thecomputer dialog window 801 as implemented in the preferred embodiment ofthe invention. A simplified CAD drawing file 810 of the first floor of abuilding is displayed behind the computer dialog box 801. Although theCAD drawing file displayed in FIG. 8 is of a single floor of a building,one skilled in the art could see how much more complex buildingstructures that include multiple floors, terrain, or any other physicalstructure could be represented. The CAD drawing file in FIG. 8 containsfour layers, named “0”, “Floor-1”, “Text-1”, and “Window-1” These aredisplayed in the computer dialog box 802 and are available for thedesigner to select. The designer is free to select one or more of thelayers from the list, as shown in FIG. 8. Once one or more layers areselected, the designer can perform several functions on the graphicalentities that belong to the selected layers. In FIG. 8, the “Windows-1”layer has been selected. Several of the graphical entities in thedrawing file 808 belong to the “Windows-1” layer. By selecting theDelete Entities button 803, the designer can automatically erase allentities belonging to layer “Windows-1”. Alternately, by selecting theProcess Selection button 807, the designer can automatically convert allentities belonging to layer “Windows-1” into a selected category ofpartition/obstruction. The choice of partition/obstruction category isselected by the designer using the pull-down list 806, and the height ofthe partition/obstruction is selected by the designer using the edit box805. Using the mouse or other computer pointing device, the designerselects one or more layers 802, selects a certain partition/obstructioncategory 806, identifies a height 805, and then selects the ProcessSelection button 807. The preferred embodiment of the invention thenautomatically converts all graphical entities belonging to the selectedlayers into partitions/obstructions of the selected category 806 andselected height 805. In FIG. 8, all graphical entities 808 belonging tothe selected layer “Windows-1” would be converted intopartitions/obstructions of type “Glass Doors and Windows” 805 and eachwould be set to be 10.83 feet tall 806. Many variations on this conceptcan be practiced within the ambit of this invention.

[0083] Referring now to FIG. 9, there is shown the same CAD file asshown in FIG. 8 following the automatic processing of all graphicalentities on layer “Windows-1”. The graphical entities that comprisedlayer “Windows-1” have been replaced with 3-D obstructions 901 whoseheight, attenuation, reflectivity, and other electromechanical andaesthetic properties correspond to those of the “Glass Doors-Windows”category of 3-D environmental partitions/obstructions selected duringthe process discussed above and using the computer dialog box shown inFIG. 8. In FIG. 9, the remaining graphical entities 902 have not beenaltered as they did not belong to layer “Windows-1”. The designer isfree to repeat the process in similar fashion for other CAD file layersto continue developing the 3-D environmental model of the facility.

[0084] This functionality represents a dramatic improvement over priorart by rapidly enabling the conversion of CAD drawing files intothree-dimensional representations of any given environment suitable foruse in the prediction of wireless communication system performance.

[0085] Referring now to FIG. 4, if the user starts with a previouslydrawn CAD drawing, the following steps outline typical procedures forformatting drawings. Methods for implementing this outline are discussedbelow.

[0086] First, the CAD drawing is input in function block 201. The userthen decides what extraneous drawing objects to remove (e.g., doors,labels, borders, drawing scales, stairs, etc.) in function block 202.Remaining objects are formatted using drawing commands, as describedabove, in function block 203. Partition colors and descriptions areadjusted, as desired in function block 204. After formatting allobjects, the drawing is verified in function block 206.

[0087] In the preferred embodiment, verification is an automatedsequential process that takes the user through a series of procedures,as listed below, to determine that all necessary data has been enteredconsistently. In alternative embodiments, the order of the proceduresand functions of each procedure can be altered, merged, expanded,modified, or even omitted depending on the judgment of one skilled inthe art. The verification process can also be fully automated, withoutrequiring user interaction. The preferred embodiment currently providesfor the following steps:

[0088] Scale Drawing is used to scale a drawing to the proper size basedon the known size of a particular object in the drawing.

[0089] Align Building Floors assists in aligning floors in a drawingafter the different floors have been assembled in the drawing.

[0090] Ceiling Height allows the user to adjust the heights of ceilingsin either meters or feet.

[0091] Set Partition Labels and Colors permits the user to set andmodify the partition labels and the colors of the partitions. The heightmay also be modified. If the partitions already exist in a drawing, theuser can use this command to globally change the color of partitions orthe partition's name.

[0092] Set Origin of Building Coordinate System allows the user tospecify a reference point which to be stored in the drawing database.This point is important for assembling drawings so that the point canautomatically align the drawings.

[0093] Set Environmental/Path Loss Parameters allows modification ofpartition labels, path loss parameters, and electrical characteristicssuch as attenuation parameters.

[0094] Create Boundary creates an invisible boundary around a drawing toguide the predictive models so that the predictions/calculations arereasonably bounded in the space within the database.

[0095] Create Legend allows the user to enter pertinent informationabout a drawing, and gives the user options to size the legend relativeto the current window and options to add additional information to thelegend such as a partition color legend, a contour color legend, and ameasurement data color legend.

[0096] The Remove-Purge Unnecessary Drawing Information command must beselected manually to ensure appropriate purging of unused drawingobjects.

[0097] If the format definition of the database is modified, it would beapparent to one skilled in the art how to change the method ofverification to accommodate these modifications. It would also beapparent to one skilled in the art how to modify and extend existingdrawing or CAD packages to perform the method of the invention.

[0098] Referring to FIG. 5, if the user starts from scratch and intendsto implement a complete vector database, formatting a drawing willconsist, only of drawing entities in function block 203, and assigningpartition information to the drawing in function block 204.

[0099] In the preferred embodiment, partitions are drawn and existingpartitions can be modified. Any entity or drawing object can beconverted into a formatted partition on a particular floor. The type ofpartition of a previously formatted entity can be modified. The floor onwhich a particular formatted object resides can also be changed. Objectswill still remain visible in the drawing after converting them topartitions on other floors. These objects may be hidden at the user'sdiscretion. A user can display partition information by selectingobjects in the drawing requesting partition information in the commandmenu. A text window containing the returned information regarding theobject's type, location, length, and electrical attributes such asattenuation factor is displayed.

[0100] If more than one drawing is used to define the environment, theymust be assembled before final verification. An automated procedurecombining several separate single floor drawings into one multi-flooreddrawing may be executed.

[0101] Finally, the drawing is verified in function block 206, asdescribed above. This verification will automatically make correctionsto the legend that may have been corrupted after assembling severaldrawings into one file. Methods for formatting a drawing from scratchare discussed below.

[0102] Referring now to FIG. 6, a method is shown to format a rasterimage into a drawing that can be used for modeling. Because computermonitors represent images by displaying them on a grid, both vector andraster images are displayed on screen as small squares or dots known aspixels. Raster images only consist of a rectangular grid of pixels.

[0103] The image file formats supported by the present invention includethe most common formats used in major technical imaging applicationareas: computer graphics, document management, and mapping andgeographic information systems (GIS). The present invention determinesthe file format from the file contents, not from the file extension.Thus, additional formats could be added easily by including theirtranslation parameters in the method.

[0104] Often times only a scanned image of a floor plan is available, asshown in FIG. 2. A user can insert a raster or bitmapped black andwhite, 8-bit gray, 8-bit color, or 24-bit color image file into thedrawing. Users can insert images in a variety of formats, currentlyincluding BMP, TIF, RLE, JPG, GIF, and TGA. More than one image can bedisplayed in any viewport, and the number and size of images is notlimited. Once the raster image is no longer needed, the user can detachthe image from the drawing.

[0105] There are two preferred ways that a scanned image can beformatted. The first approach for formatting a raster image is shown inFIG. 6A. First the current floor is set in function block 401. In a newdrawing, this creates the necessary floor layers based upon the user'sselection. Therefore, any newly drawn partitions will reside on thecurrent floor as chosen by the user. Then the image is imported infunction block 402 and scaled in function block 403. Finally the drawingis verified in function block 404. Since this drawing originally did notcontain any vector objects, the drawing database consists only of animage of the given environment that has been scaled to the properdimensions. It does not contain information with regard to physicalobjects within the environment. Depending on the application, this maybe sufficient for engineering use, for instance, when a wirelesspropagation prediction model only uses distance and does not rely onknowledge of the physical environment.

[0106] The second approach for formatting a raster image is shown inFIG. 6B. This method is similar to the method shown in FIG. 6A with theaddition of function block 405. The scanned image is “traced” by theuser to draw partitions and other obstructions prior to verification infunction block 404. This method is similar to drawing a vector baseddrawing from scratch, except that the scanned image provides a traceguide. The end result is a drawing that can be used by all wirelesssystem prediction models, including those which rely on knowledge of thephysical environment.

[0107] A distinct advantage of the present invention is that a truethree-dimensional environment is rendered from the drawings and storedin the database. The ceiling heights (or building heights) that arespecified are used to determine the vertical height of any partitionsfound on a given floor. A height is defined for a category of partitionsand this defines the object's height for each entity in that category.This is done automatically during the formatting process. Thus, eventhough the formatting process was strictly two-dimensional in nature,when the formatting of a drawing is completed, the resulting drawing isa true three-dimensional environment. The user can see thethree-dimensional building structure by altering the viewpoint.

[0108] The present invention can be used to create single floor drawingsthat can later be assembled into one multi-floored drawing or it can beused to create one or several multi-floored drawings all at once. Aftercreating a single floor, all entities that are not partitions should beremoved from the drawing. Thus, if a raster image was used as areference for tracing partitions, it should be erased once the tracingis complete. The method provides assistance to the user to distinguishbetween partition and non-partition objects. Typically, objects referredto as formatted objects are partition objects and objects referred to asunformatted objects are non-partition objects.

[0109] The final stage of formatting a drawing involves severalverification steps. These steps are automatically sequenced, asdescribed above. Before each step is performed, the user is askedwhether that step has yet been performed. If the user answers “Yes”,then that step is skipped and the user is asked about the next step.Otherwise, the current step is performed and the user is prompted forany necessary information. When all steps have been completed, thedrawing is saved. Unnecessary drawing information should then be purged.The formatted drawing should then be saved again.

[0110] This formatted drawing can now be used in any number ofapplications. Specifically, it may be used in wireless communicationsystem engineering, planning and management tools for in-building ormicrocell wireless systems, for instance as described in the co-pendingapplications: Ser. No. 09/318,842; Ser. No. 09/318,840; and Ser. No.09/221,985, the complete contents of each being herein incorporated byreference. It may also be useful in any other number of applicationsthat require a 3-D model of a building, campus or urban environment.

[0111] While the invention has been described in terms of a singlepreferred embodiment, those skilled in the art will recognize that theinvention can be practiced with modification within the spirit and scopeof the appended claims.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is as follows:
 1. A method for manipulatingdata from any environment in the world to construct a database that canbe used to generate definitions of the user's physical environmentincluding buildings, terrain and other site parameters, comprising thesteps of: (a) creating and formatting a plurality of objects defining anenvironment of floors, walls, partitions, buildings, building complexesor compounds, terrain, foliage or other sites or obstructions; (b)verifying the sufficiency of said plurality of objects to ensure auseful definition of said environment and notifying a user of results ofsaid verification of sufficiency; and (c) generating a set of formatteddata in a form transportable to and usable by an engineering planningmodel or other application, said set of formatted data including atleast one layer which includes grouped objects of said plurality ofobjects.
 2. A method as recited in claim 1, said method furthercomprising at least one of the steps: (d) inputting existing data,vectors or drawing objects, said existing data, vectors or drawingobjects either partially or fully describing said environment; and (e)removing extraneous drawing objects to simplify said definition of saidenvironment; wherein steps (d) and (e) may be performed before or afterstep (a), if data exists that fully or partially defines saidenvironment.
 3. A method as recited in claim 2, wherein said existingdata is in the form of raster files, or in the form of vector files,wherein said raster files are selected from the group consisting ofWindows Bitmaps (BMP), Joint Photographic Experts Group format (JPEG),Graphical Interchange Format (GIF), Tagged-Image File Format (TIFF),Targa format (TGA), PICT, and Postscript, and wherein said vector filesare selected from the group consisting of AutoCAD (DWG), AutoDesk (DXF),AutoDesk (DWF) and Windows MetaFile (WMF).
 4. A method as recited inclaim 1, said method further comprising the step of rendering athree-dimensional view of said environment, wherein said step ofrendering a three-dimensional view may be performed at any time after atleast one of said plurality of objects has been created.
 5. A method asrecited in claim 4, wherein said rendering step includes the step ofselecting a three-dimensional view of a selected perspective of saidenvironment.
 6. A method as recited in claim 1, wherein step (a) furthercomprises the step of adjusting partition colors, and physical andelectrical descriptions of said partitions.
 7. A method as recited inclaim 1, wherein said formatted data defines said environment and eachsaid object is associated with at least one of the group consisting of aspecific location in said environment, an attenuation factor, a color, aheight, a surface roughness value, a reflectivity value, an electricalvalue, a mechanical value, and an aesthetic value.
 8. A method asrecited in claim 1, wherein step (b) automatically prompts a user toverify that each piece of necessary information to define saidenvironment has been added to said definition of said environment beforeexecuting the verification of said each piece of necessary information,and if said user answers in the negative, prompts said user to entermissing information before proceeding.
 9. A method as recited in claim1, wherein said formatted data comprises at least one vectorized drawingof said environment.
 10. The method as recited in claim 1 furthercomprising the step of simultaneously converting said grouped objects insaid at least one layer to a selected category.
 11. The method asrecited in claim 1 further comprising the step of simultaneouslydesignating dimensions of said grouped objects in said at least onelayer.
 12. An apparatus for manipulating data from any environment inthe world to construct a database that can be used to generatedefinitions of the user's physical environment including buildings,terrain and other site parameters, comprising: means for creating andformatting a plurality of objects defining an environment of floors,walls, partitions, buildings, building complexes or compounds, terrain,foliage or other sites or obstructions; and means for generating a setof formatted data in a form transportable to and usable by anengineering planning model or other application, said set of formatteddata including at least one layer which includes grouped objects of saidplurality of objects.